addLogging

Module to apply "printf() debugging", trought metaprograming every time you call a function

Installation

npm install addLogging --save

Usage

function addLogging (code) {
  const ast = esprima.parse(code, { ecmaVersion: esprima.latestEcmaVersion, loc: true });
  estraverse.traverse(ast, {
    enter: function (node, parent) {
      if (node.type === 'FunctionDeclaration' ||
        node.type === 'FunctionExpression' ||
        node.type === 'ArrowFunctionExpression') {
        addBeforeCode(node);
      }
    }
  });
  return escodegen.generate(ast);
}

function addBeforeCode(node) {
  let param_name = [];
  node.params.forEach(function (i) { param_name.push("${ " + i.name + " }") });
  param_name = param_name.join(', ');
  let name = node.id ? node.id.name : '<anonymous function>';
  let beforeCode = `console.log(\`Entering ${name}(${param_name}) at line ${node.loc.start.line}\`);`;
  let beforeNodes = esprima.parse(beforeCode, { ecmaVersion: 6 }).body; // Is an Array of ASTs
  node.body.body = beforeNodes.concat(node.body.body);
}

console.log(addLoggin(<your-code-goes-here>));

Tests

npm test

Constributing

Try to use a consist style with the already existing code, avoid monster commits.
If you consider the contribution to be big, create a pr and add the tag [WIP] so others can watch over the process

Release History

• 0.1.0 Initial release

Documentation

Table of Contents

• addLogging
  • Parameters
• addBeforeCode
  • Parameters

addLogging

Write a literal console.log() function with information of the funcion itself

Parameters

• code string Code in string form

Returns any The result code in string form

addBeforeCode

Transforms the node of interest

Parameters

• node node node of the AST with the type of a function